New frontiers in pediatric Allo-SCT: novel approaches for children and adolescents with ALL.

Although most children with ALL can be cured by chemotherapy approaches, allogeneic hematopoietic cell transplant (HCT) therapy offers a better chance of cure to selected high-risk patients in first remission and most children who relapse. Although transplant-related mortality has decreased significantly in the past decade, relapse remains high after HCT for ALL; developing strategies to decrease relapse and improve survival are vital. Recent studies have shown that relapse risk can be accurately defined using measurements of minimal residual disease (MRD) both pre- and post-HCT and by knowing whether patients get GVHD in the first 2 months after transplant. With these risk definitions in hand, investigators are now applying novel agents and immunotherapeutic methods in attempt to lower MRD before transplant and modulate the GVL effect after transplant. With powerful new immunological approaches coming on line, the transplant process itself will likely expand to include pre and/or post-HCT interventions aimed at reducing relapse.